Moix stepped down on Thursday a day after he confirmed that he had a 25-percent stake in a company in Panama, which he shared with his siblings and had inherited from his father.

Moix’s resignation could be viewed as a victory for opposition parties, which had repeatedly criticized the way he handled some cases involving the ruling People's Party (PP).

Moix was appointed as anti-corruption prosecutor in February.

Spanish newspapers published stories in April, claiming that Moix had tried to hinder a probe into the conduct of people from PP's Madrid branch. The reports sparked increasing calls within the opposition for Moix’s resignation although he has denied any wrongdoing.

The resignation, however, was not welcome among Spain’s senior officials as the public prosecutor, Jose Manuel Maza, defended Moix's track record.

"I'm satisfied that there is absolutely nothing in the way he behaved that has been irregular or illegal," Maza said while announcing the anti-corruption chief's resignation, adding that his office found that Moix had never acted illegally or inappropriately.

PP’s leader and Spanish Prime Minister Mariano Rajoy has also felt increasing pressure for the appointment of Moix, especially at a time when he is faced with strong opposition in his minority government.

Rajoy has sought to distance himself from corruption scandals, which have mired his party and hugely affected the PP’s support among the public.

The government has steadfastly defended Moix against allegations of influence-peddling in dealing with corruption cases. However, revelations that his family held an offshore company share in Panama seem to be the last straw.